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how to catch the jquery ajax function return value in another variable

I am looking to store a value which is return by the AJAX function, here is the my code, in the AJAX success it is showing well, but when am storing that data which is saying undefined.
The following serviceNumber, which I am storing the enCrypt return value
var serviceNumber = enCrypt(typeofServiceNumber);// when am catching the function data which is saying "undefined"
the following code is my ajax function
function enCrypt(id) {
if (id > 0) {
$.ajax({
url: $("baseUrl").html() + "JobProfiles/Encryption",
type: "POST",
dataType: "json",
data: { Id: id },
success: function (encdata) {
return encdata;
},
error: function (data) {
$('#loading').hide();
}
});
}
}
Can you help me to know what is wrong in my code? Thanks in advance.

You can't use return like this, because the function is async + it's a function in a function...so actually yeah you cant return there xD
Just do something like:
enCrypt(typeofServiceNumber);
//and in your ajax:
success: function (encdata) {
go_on(encdata);
},
//and then
function go_on(serviceNumber)
{
//here you can use it :D
}

just add the
cache: false,
async: false,
to you ajax function
function enCrypt(id) {
var encnum;
$.ajax({
url: $("baseUrl").html() + "JobProfiles/EncodeIds",
type: "POST",
cache: false,
async: false,
dataType: "Json",
data: { Ids: id },
success: function (encdata) {
encnum = encdata;
},
error: function (data) {
$('#loading').hide();
}
});
return encnum;
}

Jquery Ajax Call, doesn't call Success or Error [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
How do I return the response from an asynchronous call?
I am using Jquery Ajax to call a service to update a value.
function ChangePurpose(Vid, PurId) {
var Success = false;
$.ajax({
type: "POST",
url: "CHService.asmx/SavePurpose",
dataType: "text",
data: JSON.stringify({ Vid: Vid, PurpId: PurId }),
contentType: "application/json; charset=utf-8",
success: function (data) {
Success = true;//doesn't go here
},
error: function (textStatus, errorThrown) {
Success = false;//doesn't go here
}
});
//done after here
return Success;
}
and Service:
[WebMethod]
public string SavePurpose(int Vid, int PurpId)
{
try
{
CHData.UpdatePurpose(Vid, PurpId);
//List<IDName> abc = new List<IDName>();
//abc.Add(new IDName { Name=1, value="Success" });
return "Success";
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
}
the service is being called Successfully from the AJAX. Value is also being Changed. But after the Service, success: or error: functions are not being called, in this case success should have been called but it is not working.
I used firebug and found that, the success or error functions are being skipped and goes directly to return Success;
Can't seem to find what's the problem with the code.
Update:
adding async: false fixed the problem

change your code to:
function ChangePurpose(Vid, PurId) {
var Success = false;
$.ajax({
type: "POST",
url: "CHService.asmx/SavePurpose",
dataType: "text",
async: false,
data: JSON.stringify({ Vid: Vid, PurpId: PurId }),
contentType: "application/json; charset=utf-8",
success: function (data) {
Success = true;
},
error: function (textStatus, errorThrown) {
Success = false;
}
});
//done after here
return Success;
}
You can only return the values from a synchronous function. Otherwise you will have to make a callback.
So I just added async:false, to your ajax call
Update:
jquery ajax calls are asynchronous by default. So success & error functions will be called when the ajax load is complete. But your return statement will be executed just after the ajax call is started.
A better approach will be:
// callbackfn is the pointer to any function that needs to be called
function ChangePurpose(Vid, PurId, callbackfn) {
var Success = false;
$.ajax({
type: "POST",
url: "CHService.asmx/SavePurpose",
dataType: "text",
data: JSON.stringify({ Vid: Vid, PurpId: PurId }),
contentType: "application/json; charset=utf-8",
success: function (data) {
callbackfn(data)
},
error: function (textStatus, errorThrown) {
callbackfn("Error getting the data")
}
});
}
function Callback(data)
{
alert(data);
}
and call the ajax as:
// Callback is the callback-function that needs to be called when asynchronous call is complete
ChangePurpose(Vid, PurId, Callback);

Try to encapsulate the ajax call into a function and set the async option to false. Note that this option is deprecated since jQuery 1.8.
function foo() {
var myajax = $.ajax({
type: "POST",
url: "CHService.asmx/SavePurpose",
dataType: "text",
data: JSON.stringify({ Vid: Vid, PurpId: PurId }),
contentType: "application/json; charset=utf-8",
async: false, //add this
});
return myajax.responseText;
}
You can do this also:
$.ajax({
type: "POST",
url: "CHService.asmx/SavePurpose",
dataType: "text",
data: JSON.stringify({ Vid: Vid, PurpId: PurId }),
contentType: "application/json; charset=utf-8",
async: false, //add this
}).done(function ( data ) {
Success = true;
}).fail(function ( data ) {
Success = false;
});
You can read more about the jqXHR jQuery Object

Why can't I do .ajax ( return data; )? jQuery

I'm trying to get my function to return the data it got into another function but it doesn't seem to work? How can I get it to return the data?
function playerid(playername) {
$.ajax({
type: "POST",
url: "fn.php?playerid",
data: "playername="+playername,
success: function(data) {
//$("#test").text(data);
return data;
}
});
}
I want to use it in another function like this
showBids(playerid(ui.item.value));
function showBids(playerid) {
$.ajax({
type: "POST",
url: "poll.php?",
async: true,
dataType: 'json',
timeout: 50000,
data: "playerid="+playerid,
success: function(data) {
//.each(data, function(k ,v) {
//})
//$("#current_high").append(data);
setTimeout("getData()", 1000);
}
});

First of all, your playerid() does not return anything, so what do you want to use? It has only $.ajax() call in it, no return statement (one of the callbacks in $.ajax() has return statement, but see below).
Secondly, JavaScript does some things asynchonously, otherwise every interface element would need to wait to react to user action until the AJAX call returns from the server.
Use event-based approach, by passing callbacks to some functions. Then, after they finish, just call the callbacks passing them the result:
function getplayerid(playername, callback) {
$.ajax({
type: "POST",
url: "fn.php?playerid",
data: "playername="+playername,
success: function(data) {
//$("#test").text(data);
callback(data);
}
});
}
and then use it like that:
getplayerid(ui.item.value, showBids);
(notice function name change since it does not actually return player ID, it gets it and passes it to callback)

You could try to use syncronous Ajax:
function playerid(playername) {
return $.ajax({
type: "POST",
url: "fn.php?playerid",
data: "playername="+playername,
async : false //making Ajax syncronous
}).responseText;
}
Otherwise you need to use showBids function as callback:
function playerid(playername, callback) {
$.ajax({
type: "POST",
url: "fn.php?playerid",
data: "playername="+playername,
success: function(data) {
callback(data);
}
});
}
//Usage
playerid(ui.item.value,showBids);

"undefined" for alerting an ajax call response , why?

i am trying to alert the return value captured by the ajax request. The web method it is refering is returning a boolean value of true or false, and when i am trying to access it outside the ajax method it gives a message "undefined" :?
<script type="text/javascript" language="javascript">
$(document).ready(function () {
var authInfo;
$.ajax({
type: "POST",
url: "service.asmx/getAuthInfo",
data: "{}",
contentType: "application/json; charset=utf-8",
dataType: "json",
success: function (msg) {
authInfo = msg.d;
},
});
alert(authInfo);
});
</script>
why is the alert(authInfo) giving me as "undefined" ?? Please help !
where does this piece of code fit on the above context ?
if(auhthInfo){
$(".ansitem").editable('FetchUpdate.aspx', {
style: 'background-color:inherit;',
type: 'textarea',
indicator: '<img src="spinner.gif">',
event: 'dblclick',
onblur: 'submit',
submitdata: function (value, settings) {
return { orgval: value};
},
});
};

Your "$.ajax()" call is asynchronous, and thus the results are not available until the response is returned from the server.
If you put your "alert()" inside the "success" callback, it should work (if the HTTP transaction works).

EDITED TO HANDLE YOUR NEW CODE:
<script type="text/javascript" language="javascript">
$(document).ready(function () {
var authInfo;
$.ajax({
type: "POST",
url: "service.asmx/getAuthInfo",
data: "{}",
contentType: "application/json; charset=utf-8",
dataType: "json",
success: function (msg) {
// alert(msg.d); // here it will work as it is only called when it succeeds.
MyHanlder(msg);
},
});
// alert(authInfo); // here authinfo has no value as the AJAX call may not have returned.
});
function MyHandler(msg) {
if(msg.d){
$(".ansitem").editable('FetchUpdate.aspx', {
style: 'background-color:inherit;',
type: 'textarea',
indicator: '<img src="spinner.gif">',
event: 'dblclick',
onblur: 'submit',
submitdata: function (value, settings) { return { orgval: value}; },
});
};
}
</script>

The request and the response that you get via ajax calls are asynchronous. I think it is not possible to alert the value that you get in response at the end of ready function because you are not assured that you will be getting your response before the function completes execution.

You are alerting the authInfo variable before the actual ajax call have returned. If you try this:
success:function(msg) {
authInfo = msg.d;
alert(authInfo);
}
I think you will get the correct result.

Because the AJAX call is done asynchronously, the alert does not have the value at the time of execution. If you place the alert inside the success function you should see the appropriate results. I also noticed you have an extra comma in the $.ajax parameters after the success function parameter.

It appears:
alert(authInfo);
Is running immediately when your document is ready.
However, the variable is not being initialized until after the AJAX call completes.
Try moving the alert to:
$.ajax({
type: "POST",
url: "service.asmx/getAuthInfo",
data: "{}",
contentType: "application/json; charset=utf-8",
dataType: "json",
success: function (msg) {
authInfo = msg.d;
alert(authInfo);
},
});
If you need to do anything more complex with the value, you can try re-factoring the code into another function:
function onSuccess(msg)
{
if(msg.d)
{
window.alert('The value is true!');
}
else
{
window.alert('The value is false!')
}
}
$.ajax({
type: "POST",
url: "service.asmx/getAuthInfo",
data: "{}",
contentType: "application/json; charset=utf-8",
dataType: "json",
success: onSuccess,
});

ajax request not working on IE

function VReload()
{
$.ajax({
type: "GET",
url: "/foo/",
success: function (data) {
$("#myid").html(data);
}
});
}
$(document).ready(function() {
setInterval('VReload()', 1000)
});
This piece of code is working fine on Mozilla and chrome but not on IE. Ajax call is not firing on IE. What could be the reason.

Switch off caching by doing this:
$.ajax({
type: "GET",
cache: false,
url: "/foo/",
success: function (data) {
$("#myid").html(data);
}
});

set cache false
$.ajaxSetup({ cache: false });
or
$.ajax({
cache: false,
//other options
});

Try this:
function VReload()
{
var timestamp = new Date();
$.ajax({
type: "GET",
url: "/foo/" + "&timestamp=" + timestamp.getTime(),
success: function (data) {
$("#myid").html(data);
}
});
}
$(document).ready(function() {
setInterval('VReload()', 1000)
});

use jQuery's $.get() function
$.get('/foo/', {}, function(data){
// whatever
});